An Avidin-Biotin Conjugation Technique for Presenting Target Antigens on Mycobacterium bovis BCG

Begin with a suspension of Mycobacterium bovis BCG, treated with a non-ionic surfactant, to prevent bacterial clumping.

Next, add a biotinylation reagent and incubate.

This biotinylation reagent, a complex of biotin complexed to a functional linker, facilitates binding biotin molecules to bacterial surface proteins, labeling bacteria.

Post-incubation, centrifuge the biotin-labeled bacterial suspension to remove unreacted biotinylation reagent.

Resuspend the bacteria in a buffer. Add a solution of avidin-fusion protein, a recombinant protein comprising a target antigen domain fused to monomeric avidin.

During incubation, avidin binds to biotin, facilitating bacterial surface modification with target antigens.

Centrifuge the suspension to remove unbound fusion proteins.

Resuspend the antigen-coated bacteria in a buffer containing a non-ionic surfactant. The antigen coating on the bacteria can enhance its property to trigger immune responses.